code: def _subst_vars(s, local_vars):
      try:
          return s.format(**local_vars)
      except KeyError as var:
          try:
              return s.format(**os.environ)
          except KeyError:
              raise AttributeError(f"{var}") from None
  
imports: import os
  import sys
  import threading
  from os.path import realpath
label_desc: Use image node_id 5 for calling a global function with example usage: _subst_vars(s, local_vars) and returns: s, s